The Concept Assessment Kit (CAK) Scales

One of the most important phases in a child's development is the transition from a prelogical to a logical mode of thought. In Piaget's theory, the concept of conservation not only signals this cognitive change, but also represents a crucial intellectual attribute in and of itself. When a child is able to conserve, he recognizes that certain properties, such as substance, weight, volume, or number, remain unchanged in the face of certain transformations, such as changes in the object's form, shape, color, or position.

THE CONCEPT ASSESSMENT KIT - CONSERVATION consists of three rating scales. Forms A and B are parallel forms and each includes the following six tasks: Two-Dimensional Space, Number, Substance, Continuous Quantity, Weight, and Discontinuous Quantity. Form C measures a slightly different dimension of conservation and includes the following two tasks: Area and Length. On each scale, the child's level of conservation is determined by conservation behavior and comprehension of the principle involved. Conservation behavior refers to the child's judgment of the relative quantity of two objects, one of which has just been manipulated by the examiner. Comprehension is assessed by the child's explanation for his judgment.